1. Field
This relates to a light emitting device.
2. Background
A light emitting diode (LED) is a semiconductor light emitting device that converts current to light. The wavelength of light emitted by such an LED depends on a band-gap of the semiconductor material used in the LED, the band gap representing an energy difference between a valence band and a conduction band. Recently, LEDs have been used as a light source for displays such as liquid crystal displays (LCDs), a light source for automobiles, and a light source for other types of lighting devices. An LED may emit white light by using phosphor materials or may emit various colors by combining LEDs having various colors. However, when the LEDs are used in certain applications, the efficiency of the LEDs may be significantly degraded.